Hi Morimoto-san
On 2018/12/06 14:38, Kuninori Morimoto wrote:
Hi Jiada
SMSTPCR922 controls input of two clocks "S0D1ϕ" and "S0D4ϕ",
Ahh, OK I could check it via Block diagram. But it is "Module stop" for these, anyway. "Module stop" and "S0D1ϕ/S0D4ϕ" are completely different clocks.
Yes, "module stop" is different from "S0D1ϕ/S0D4ϕ", both clk_i and avb_counter8's parent clock is same "module stop" clock, which is <&cpg CPG_MOD 922>, it is a shared gate clock between avb_counter8 and clk_i
"S0D4ϕ" is input to BRGA, "S0D1ϕ" is input to avb_counter8
It seems we need to update "clk_i" portion first for this purpose. Then, we need to consider about Gen2 vs Gen3, etc, etc... It seems we can't keep patch simple...
Yes, I know it's not simple, so I want to discuss with you, how we can proceed on this topic, by adding avb_counter8, rcar audio can support arbitrary clock rate, which is a desired feature, IMO
3rd, we need to create new clock/handler for avb_counter8 / audio_clk_div3 / avb_div8 for "internal" purpose, and need to create avb_adg_syn[] clock for "external" purpose for EAVB/IF. Your code is creating / registering adg->clkavb[], but it is for avb_counter8 in my understanding. We don't need to register it as formal clock IMO.
I agree, besides avb_counter8 there are other clocks which need to be added as you have mentioned, in this patch-set, I only added avb_counter8, because I want to keep the patch-set simple, other clocks can be added later.
No, No, No. avb_counter8 is just "internal" clock, and one of parent clock for avb_div8 which is needed for avb_adg_syn[]. We need to control/register is avb_adg_syn[], not avb_counter8.
Your approach on this patch is very "Quick-Hack". I have no objection for out-of-tree patches. But, "Quick-Hack approach with changing formal DT on upstream" is nightmare.
avb_counter8 is registered as formal clock is because, there is use case that EAVB-IF may use avb_div8, and avb_counter8 is input to avb_div8. if keeps avb_counter8 'internal', I am not sure how EAVB-IF can set clock rate for avb_counter8
EAVB/IF driver setups avb_adg_syn[]. Then, ADG considers/searchs avb_counter8/avb_div8/audio_clk_div3 settings internally. Don't control avb_counter8 directly from EAVB.
OK, I think I understand your point, which avb_counter8 / avb_div8/audio_clk_div3 need to be used, only need to be considered by adg internally.
Thanks, Jiada
Best regards
Kuninori Morimoto